1. Field of the Invention
The present invention relates to railcars for transporting vehicles, typically also called vehicle carrier railcars, and more particularly, directed toward a door system for an aluminum vehicle carrier railcar.
2. Background Information
Railcars have long been used for transporting vehicles long distances, in particular automobiles and light trucks, generally from the point of manufacture or import location to dealerships or locations where the automobiles or trucks can be subsequently transported by truck. As with other freight, a vehicle carrying railcar is designed to carry a maximum number of motor vehicles in each railcar. This has lead to the development of a bi-level or tri-level vehicle carrier railcar. In addition to the desire to carry a maximum number of vehicles on each vehicle carrier railcar, the existing railcars have been designed to minimize damage or vandalism of the vehicles such that many vehicle carrying railcars are designed as an enclosed structure. Conventionally, the existing vehicle carrier railcars are formed of steel that presents other problems for the railcar including additional weight and rust or corrosion in the cargo interior. Some attempts have been made to address this, such as a fiberglass panel articulated railcar disclosed in U.S. Pat. No. 5,511,491.
A number of end door systems are known for railcars, such as vehicle carrier railcars. U.S. Pat. No. 3,911,831 discloses a folding end door comprised of hinged panels. The panels of the door fold in overlying relationship to one another in the open position and unfold across the end of the railcar in the closed position. In the open position, the folded panels are positioned inside the railcar adjacent the sidewalls resulting in a reduced loading area. Moreover, in the closed position the panels do not extend across the gambrel roof of the railcar to prevent access into the railcar. Other folding end door systems are illustrated in U.S. Pat. Nos. 5,979,335 and 5,742,192 in which a pair of hinged three-panel doors close the respective ends of the railcar. Each three-panel door extends the entire height of the car body and extends from one side of the car body to the centerline of the car body. Each three-panel door may be swung open into a position in which the three vertically extending segments of each door, a corner panel, a middle panel and a center panel, nest alongside each other inside and adjacent the respective corner post of the car body.
U.S. Pat. No. 3,996,860 discloses a double bi-fold door assembly for the end opening of a vehicle, wherein each assembly includes an inner and an outer panel which are manipulated from the closed positioned to an open stored position by folding the inner panel 180 degrees into an overlaying arrangement with the outer panel and there after pivoting the two adjacent panels 270 degrees about the side edge of the car end opening to place each bi-fold door assembly in a stored position parallel to and outside of the side wall of the railcar.
U.S. Pat. No. 4,084,516 discloses a double bi-fold door assembly for the end opening of a vehicle, wherein each assembly includes an inner and an outer panel hinges together such that when opened the two inside panels are juxtaposed to each other and the two adjacent panels are placed in a stored position parallel to the side wall of the railcar. The folded assembly is pushed longitudinally toward the interior of the railcar until the folded door assembly is within the railcar interior.
U.S. Pat. No. 4,240,357 discloses a set of multiple paneled door assemblies for the end opening of a vehicle, wherein each assembly includes a plurality of hinged panels connected to permit the swinging of the panels outwardly or inwardly toward positions parallel to the wall of the railcar. Once in the open position the door assemblies may be selectively moved along the inside railcar side wall.
U.S. Pat. No. 4,318,349 discloses a double bi-fold door assembly for a vehicle end opening, wherein each assembly includes an inner and an outer panel hinged together with the inner panel being initially folded inwardly then outwardly over the end of the outer panel. The two folded panels are subsequently pivoted into an inner recessed position substantially parallel with the ends of the sidewalls of the railcar.
U.S. Pat. No. 5,601,033 discloses a double bi-fold door assembly for each end of an articulated train railcar, wherein each assembly has a first and a second panel hinged together and pivoted together relative to the railcar to place the folded assembly adjacent the exterior of the railcar.
Some end enclosures comprise doors that slide from the closed position to a position along the inside of the sidewalls. The doors are hung from a track member that is positioned along the edge of one of the decks. A space is provided between the side of the deck and the sidewalls at the end of the railcar so that a portion of the track is spaced and substantially parallel to the sidewalls. Thus, the doors can be moved along the track to a position along the inside of the sidewalls to enable access to the interior of the railcar. A suitable guide track or rail is usually provided adjacent the bottom edges of the doors. The guide track does not hinder the operation of the door and provides security by restricting the outward movement of the lower end of the door. Thus, access may not be gained to the interior of the railcar by pulling out the bottom edges of the doors away from the opening. A door of the type being described is disclosed in more detail in U.S. Pat. No. 4,437,410.
Since the edges where the roof and sidewalls are joined are sloped, it is not possible to extend the doors upwardly to completely fill the gable space and still slide the doors back along the sidewalls. The higher portion of the door would interfere with the sloped portions of the roof. Numerous schemes have been devised to attempt to fill the gable space. Some doors are built with top portions bent inwardly so that they will not interfere with the sloped portion of the roof as shown in U.S. Pat. No. 4,437,410. In some cases, complicated folding panels close the gable portion of the space as shown in U.S. Pat. No. 4,265,183. In yet other cases, the gable space is simply left open, see U.S. Pat. No. 3,996,860 discussed above.
One manner of solving the above problem, as suggested by U.S. Pat. No. 3,995,563, is to use an end closure comprising two sliding doors which move between closed and open positions. Upon opening of the doors, each door moves into an open space on the outer side of the railcar through a vertical opening in the sidewall. Each door includes an arcuate laterally outer portion and a straight laterally inner portion attached tangent to the laterally inner edge of the arcuate portion. Each door is supported to ride on an arcuate track having the same radius of curvature as the arcuate portion of the door. The door is supported on the track by rollers attached solely to the arcuate portion.
The opening in the sidewall allows the door to cover the gable portion of the space. However, the opening in the sidewall provides an undesirable degree of access to the interior of the railcar from outside, placing the contents of the railcar in jeopardy of damage from vandalism and other outside forces. In addition, support of the door on rollers only on the arcuate portion results in a relatively weak support of the laterally inward portions of the doors.
The extension of the door through the sidewall presents problems with respect to support of the required ladder at the end of the car. In the prior art, the ladder is supported by a brace beam connected to its top end. Because the door is taller than the height of the brace beam, a slot is cut in the door to allow it to open. This slot weakens the laterally outward upper corner of the door, which may be bent back to gain access to the interior of the car.
The above problems were also addressed in U.S. Pat. No. 4,924,780 which disclosed a track mounted, sliding, multi-panel door system for a vehicle carrier railcar. The difficulty with this proposed system is the large amount of force required to open it due to the door system's excessive height and the application of force relatively far from one of the roller tacks. Furthermore, in track based systems, the rollers will develop flat spots while resting in the closed position making track based door operating systems harder to operate. Frequent adjustment and lubrication does not adequately compensate for these causes of binding. Furthermore, in automobile or vehicle carrier railcars, lubrication is undesirable, since the lubrication will find its way into the apolstered interior of the automobiles damaging the cargo. Furthermore, in the existing track based door systems, the arc of the door minimizes the vehicle drive-in clearance of the railcar when the door is in the fully open position.
Consequently, there is a need to provide a door system for a railcar, such as a vehicle railcar, which eliminates tracks, rollers, flat spots or lubrication to the greatest extent possible. There is a further need to provide an end door system for a railcar which will open and be positioned flat against the outside of the railcar and, therefore, not hinder the loading and unloading of the vehicles.